8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
1/14
W
PC
A
Worldwide Pollution
Control Association
WPCA-Entergy
Increasing Energy
Efficiency of Existing
Units Seminar
January 22, 2014
Visit our website at www.wpca.info
All presentations posted on this website are copyrighted by the Worldwide Pollution
Control Association (WPCA). Any unauthorized downloading, attempts to modify or to
incorporate into other presentations, link to other websites, or to obtain copies for any
other purposes than the training of attendees to WPCA Conferences is expressly
prohibited, unless approved in writing by the WPCA or the original presenter. TheWPCA does not assume any liability for the accuracy or contents of any materials
contained in this library which were presented and/or created by persons who were
not employees of the WPCA.
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
2/14
Louis Bondurant
January 22, 2014
Approaches to ImproveAir Preheater
Thermal Efficiency
Alstom Air Preheater
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
3/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 2
LGOT R&D Program(Low Gas Outlet Temperature)
Objective of the LGOT Program
Develop the design of the Ljungstrom air preheater for operation at gas outlet temperatures
down to 220F (105C) on coal fired boiler applications.
The Potential Benefits of LGOT
Significant reduction in Dry Gas Loss a key metric in unit heat rate
Reduced volumetric flow rates for downstream FGD, CO2 capture, etc.
ESP can benefit from reductions in both volumetric flow and fly ash resistivity
Potential Issues for LGOT Enhanced risk of air preheater acid dew point fouling problems
Added potential for low temperature corrosion from halogen acids near the H2O dew point.
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
4/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 3
Bench-Scale Test Apparatus
Fouling Test Apparatus Soot Blowing Simulator
Simulated gas flow included controlled amounts of
SO3
Water vapor
Solid particulate
Cleaning cycle
Duration of tests mimicked typical sootblowing interval
Translational movement in the path of the cleaning
nozzle mimicked rotor rotation
Tube removal required in order to clean
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
5/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 4
Pilot Scale Test Apparatus
AirSdeFan
Tower1
To atmosphere
PreheatBurner Natural Gas
GasSdeFan
Catalyst SO2
Part iculate FeederWater
Flyash
Soot blower
Tower2
Soot blower
Broken = Gas side flow
Solid = Air side flow
To atmosphere
HeatExchanger
Baghouse
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
6/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 5
Pilot Scale Test Apparatus
Gas Inlet Ducting: SO3, H2O,Flyash Injection
Preheat BurnerSystem
Instrumentation Panel
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
7/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 6
Simulated URS SBS InjectionTechnologyFull Mitigation (5ppmv SO3+ Na2SO4By-Product)
Stable Pressure Drop Response for ~ 2 Months
Tower 1 Gas Side Pressure Drops
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0 200 400 600 800 1000 1200 1400 1600 1800 2000
Elapsed Operating Time (hrs)
PressureDro
p
(inwg)
2000
2100
2200
2300
2400
2500
2600
2700
2800
2900
FlueGasFlo
w(
lb/hr)
Total Cold End Flue Gas Flow
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
8/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 7
Simulated URS SBS InjectionTechnologyFull Mitigation (5ppmv SO3+ Na2SO4By-Product)
No Significant Deposit Thickness Was Found
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
9/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 8
Conclusions from Pilot Scale TestingSimulated URS SBS Injection Technology
With SO3levels reduced to 5 ppmv
Cold layer pressure drop did not increase
No significant deposit thickness was found
With SO3levels at 10 ppmv
Rapid increases in cold layer pressure drop occurred
Significant sodium bi-sulfate deposit was found
Note: Sodium based SO3mitigation must reduce SO3concentrations to 5ppmv or less entering the air preheater
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
10/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 9
RGOT Vs LGOT Operation(Reduced Gas Outlet Temperature)
Simple modifications to an existing air heater typically cannot achieve a
220F gas outlet temperature
An increase in airflow can provide a significant reduction in gas temperature.
Co-benefit, if this this incremental hot air can be used elsewhere in the plant.
Reduced gas outlet temperature (> 220F) can be pursued in lieu of LGOT.
Basic benefits retained, implementation cost lowered significantly.
Reduced potential for corrosion, but need to stay above H2O dewpoint
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
11/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 10
RGOT OperationMeans to Accomplish
Fill empty voids in APH rotor with additionalbasket layers
Utilize special basket designs to maximize
useable space for heat transfer surface
Consolidate shallow basket layers into
single deeper layers
Modify APH rotor to more efficiently support
basket layers
Switch to more efficient types of heat
transfer surface
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
12/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 11
RGOT OperationConsiderations
Fuel compatibility
Thermodynamic limitation
Available space within the existing APH rotor
Load bearing limits on rotor bearings, rotor drive and APH structure
Ability of draft fans to accommodate expected pressure drop levels
Ability of APH sealing system and structure to operate at higher
pressure levels
Ability to maintain temperature levels above H2O dew point at all loadand ambient conditions
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
13/14
ALSTOM 2013. All rights reserved. Information contained in this document is indicative only. No representation or warranty is given or should be relied onthat it is complete or correct or will apply to any particular project. This will depend on the technical and commercial circumstances. It is provided withoutliability and is subject to change without notice. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.
Presentation title - 23/01/2014 P 12
Benefits Derived from RGOT
Reduced coal consumption (potentially as much as 3%)
Significant reduction in activated carbon required for mercury capture
Enhanced ESP performance (due to fly ash resistivity)
Reduced O&M costs associated with steam coil air preheaters
Reduced CO2 emissions resulting from improved boiler efficiency
Co-benefit if additional hot air can be used elsewhere on site
8/13/2019 Approaches to Improve Air PreHeater Thermal Efficiency by Louis Bondurant, Alstom
14/14
Top Related